Apparatus for performing analyses



May 25, 1965 A. HAACK 3,185,550

APPARATUS FOR PERFORMING ANALYSES Filed Sept. 1, 1961 Fig.4

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fig. INVEN TOR ALFRED HAACK BY @mww I ATTORNEY United States Patent 3,135,550 APPARATUS FOR PERFORMING ANALYSES Alfred Haack, Vienna, Austria, assignor to Arthur H. Thomas Company, Philadelphia, Pa., a corporation of Pennsylvania Filed Sept. 1, 1961, Ser. No. 135,570 Claims priority, application Austria, Sept. 2, 1960, A 6,735/60 3 Claims. (Cl. 23253) The invention covers an apparatus for the performance of analyses, especially for the performance of quantitative analyses of organic compounds, and consists of a flask with ground joint and ground joint stopper.

For the performance of the socalled flask method for the microanalytical quick determination of sulfur, halogens, phosphorus and other elements in organic compounds, one burns the organic compound in a flask in an atmosphere of oxygen or in the presence of an oxygen containing compound. Until now one used an Erlenmeyer flask with a ground joint stopper, wherein the stopper has a rod-like extension with a support for the substance to be analyzed. This support or sample carrier consists of a short platinum wire ending in a platinum gauze or of a spiral of quartz glass, both of which are either fused onto or into the rod-like extension of the stopper.

This prior technique results in the disadvantage that on corrosion or breakage of the platinum wire, or

quartz spiral respectively, the complete flask becomes unavailable for a certain length of time, until the stopper is repaired and a new wire or quartz spiral is fused onto or into its rod-like extension. Experience has shown that especially the platinum gauze is frequently damaged, as it becomes brittle in certain types of analysis, such as determinations of phosphorus or arsenic, even though one has used the so-called phosphorus-resistant platinum.

An object of this invention is the development of an apparatus for the performance of analyses, especially quantitative analyses of organic compounds, in which all the advantages of the flask combustion method are maintained, but the mentioned disadvantages are avoided. Other objects will appear hereinafter.

We have now an apparatus, which is less expensive, has a longer life and permits a longer period of use without interruptions. The invention covers an ap-' paratus of the above type for the performance of analyses, especially quantat-ive analyses of organic compounds, in form of a ground joint ilask with a ground joint stopper, which has a rod-like extension provided with a carrier for supporting the substance to be analyzed. According to the invention the carrier need not be firmly connected to the stopper or its rod-like extension, respectively, and can be exchanged.

Fundamentally, the stopper has only a very short extension, which can .be connected by means of a removable connecting piece of metal, rubber or plastic, especially tetrafluoroethylene (Teflon), with the sample carrier.

The removable connecting piece is preferably of a tubular form or a tube of suitable diameter so that it can be pushed over the extension of the ground joint stopper. Suitable threads on the inside of the connecting piece can be provided so that the connecting piece can be screwed onto a corresponding outer thread of the above extension. The carrier, which is preferably rodshaped, can either be merely pushed into the connecting piece or, if threads on the inside of the connecting piece and on the outside of the carrier are provided, be screwed into it.

The rod-like carrier can be made of platinum, quartz, or laboratory glass, such as is commercially available in form of Jena glass so that for each type of analysis 3,185,550 Patented May 25,1965

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the most suitable material can be used. The carrier is formed in its lower end to support the substance to be analyzed, and this lower end can be, for example, either a gauze, a spiral or a cup.

An additional disadvantage of the usual flask combustion method is the formation of a vacuum in the flask due to the combustion of the substance and the corresponding consumption of oxygen, so that on the use of a good vacuum tight ground joint the stopper is difficult to remove.

This invention includes a perpendicular groove, or

recess in the ground joint portion of the stopper and correspondingly in the ground joint at the neck of the flask the formation of a suitable enlargement or a corresponding hole for the connect-ion of the flask interior to the outside atmosphere and also for the addition of a liquid.

For the purpose of illustrating the invention there is shown in the drawings forms which are presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIGURE 1 shows schematic in cross section the apparatus as per invention in full.

FIGURES 2 and 3 show different forms of the carrier for the support of the substance to be analyzed.

FIGURE 4 shows an arrangement for the support of the carrier during the weighing of the substance.

FIGURES 5 and 6 are fragmentary views showing modifications of the present invention.

FIGURE 7 shows the ground stopper as seen from above, whereby the head of the stopper has a ground flat piece on one side (vertical plane).

FIGURE 8 is a cross sectional view along the line 88 in FIGURE 1.

The apparatus of the invention comprises the flask 1 with a ground stopper 2, the ground joint 3 of which mates with the ground joint 4 of the flask. The ground stopper 2 has a short extension 5 and a perpendicular groove 6. On turning, the ground stopper 2 may be connected with an enlargement 7 (embodiment of FIG- URES 1 and 5), or a hole 7 (embodiment of FIGURE 6) in the flask.

In its lower end the ground stopper 2 is connected through its extension 5 with a connecting piece 8 of metal, rubber or plastic, especially Teflon, which can be removed and into which one can insert from the lower end a rodlike carrier 9 for carrying the substance to be analyzed. The rod-like carrier 9 can be connected as shown in FIGURE 1, with a wire 1th and a gauze 11 attached to it,.=to provide a carrier for the substance to be analyzed.

As shown in FIGURE 2, the carrier ha can be formed on the end 11a as a spiral; or as shown in FIGURE 3 the carrier 9b can be formed on the end 1 1. as a cup. In the embodiments of FIGURES 2 and 3, the intermediate portion 16 shown in FIGURE 1 is omitted.

FIGURE 4 is an additional element =12 for the support of carrier 9, 9a or b with the corresponding parts, 10, 11 or 11' used during weighing; it has in its upper end a hole for hanging it up in the balance and can be connected with the carrier 9, 9a, or 9b also through the connecting piece 8 or a similar connecting piece of this type.

The invention offers the possibility to perform the widely used flask combustion procedure in a simpler, cheaper and more rational manner and enlarges the future possibility of wider applications in other fields.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

I claim:

1. Apparatus for performing analyses including a flask, said flask having an elongated neck portion, a ground glass stopper adapted to frictionally seat in said neck, a carrier, discrete coupling means selectively dctachably coupling said carrier to said ground glass stopper whereby said carrier is dependently extended from said ground glass stopper into the interior of said flask, and a support on said carrier remote from said stopper, said support being adapted to effect the support of a sample to be analyzed.

2. The apparatus for performing analyses of claim 1 wherein the neck of said flask has a longitudinally extending conduit in the wall thereof extending from one end of the neck to a central portion thereof, said ground glass stopper having a conduit therein extending from one end thereof opposite from said one end of said neck to the center portion thereof, said ground glass stopper conduit and said flask neck conduit overlapping when said ground glass stopper is seated in said neck and said conduits are in an aligned position, said conduits permitting gaseous communication between the interior and exterior of said flask through said neck when said ground glass stopper is rotated to a position aligning said ground glass stopper conduit with said fiask neck conduit.

3. Apparatus in accordance with claim 1 wherein said coupling means includes a flexible hollow tube, said stopper having a projection at the end thereof placed within said flask, said projection frictionally engaging said hollow tube, said carrier being frictionally engaged by said hol- 10W tube to be supported thereby from said projection.

References Cited by the Examiner UNITED STATES PATENTS 1,293,423 2/19 Hart 23292 1,482,966 2/24 Bevan 23253 2,026,890 1/36 Cross 15-611 2,320,323 5/43 Grunberg 15-611 2,582,721 1/52 Roshkind 21543 3,058,813 10/62 Barney et al 23-292 MORRIS O. WOLK, Primary Examiner.

ANTHONY SCIAMANNA, JAMES H, TAYMAN,

Examiners. 

1. APPARATUS FOR PERFORMING ANALYSES INCLUDING A FLASK, SAID FLASK HAVING AN ELONGATED NECK PORTION, A GROUND GLASS STOPPER ADAPTED TO FRICTIONALLY SEAT IN SAID NECK, A CARRIER, DISCRETE COUPLING MEANS SELECTIVELY DETACHABLY COUPLING SAID CARRIER TO SAID GROUND GLASS STOPPER WHEREBY SAID CARRIER IS DEPENDENTLY EXTENDED FROM SAID GROUND GLASS STOPPER INTO THE INTERIOR OF SAID FLASK, AND A SUPPORT OF SAID CARRIER REMOTE FROM SAID STOPPER, SAID SUPPORT BEING ADAPTED TO EFFECT THE SUPPORT OF A SAMPLE TO BE ANALYZED. 